By Zack Meisel, Cody Stavenhagen and Stephen J. Nesbitt

GOODYEAR, Ariz. — A decade ago, on a dusty baseball diamond in Puerto Rico, a veteran pitcher shared with Fernando Cruz the secrets of throwing a splitter, a pitch treated like a black-market product, a dark art best learned in the shadows and deployed at one’s own risk.

Cruz was a converted infielder pitching in winter ball back home and trying to catch on with a major league organization. He couldn’t command the splitter. “Started hitting people with it,” he said. “Started bouncing it.” But he stuck with it because, when it was right, it was like sorcery. Hitters read it as a fastball and couldn’t recover as the baseball dived below their bat path.

By the time the Cincinnati Reds signed Cruz in 2022, he had wrestled the splitter into submission. Triple-A pitching coach Casey Weathers told him, “Use it, because nobody can hit it.” Cruz made his major league debut at 32. He said he owes it all to the splitter, which has generated a .085 batting average and one of the highest whiff rates of any pitch in baseball.

“I call it my gift from God,” Cruz said.

The baseball weapon known as the “Pitch of the ‘80s” became a devastating tool Roger Clemens, Curt Schilling and John Smoltz deployed to pile up strikeouts in the ‘90s. Then it all but disappeared as it earned a reputation for wrecking pitchers’ arms due to the strain it was believed to put on the pitching elbow. Some organizations forbade its use entirely. 

That meant learning to throw the pitch required meeting with an expert in a discrete location. Eddie Guardado spread the splitter gospel in the Seattle bullpen in the mid-aughts, teaching J.J. Putz his grip as they sat on folding chairs 400 feet from home plate. Putz relayed the code to Bryan Shaw in Arizona’s pen in 2011. Ten years later, Shaw shared the secrets with Trevor Stephan in Cleveland. It was a local legend, a haunting myth passed down by word of mouth.

Now, the stigma is softening. Almost every day this spring, it seems, a big-league pitcher unveils his new splitter: Zack Wheeler with the Phillies, Hunter Greene with the Reds, Jordan Hicks with the Giants, Bryce Miller with the Mariners, Matt Manning with the Tigers. Yoshinobu Yamamoto makes his MLB debut for the Los Angeles Dodgers Thursday in Korea, after riding a feared splitter — which could immediately be the best in MLB — to a $325 million contract. Splitters accounted for 2.2 percent of all pitches last season, the highest mark since pitch-tracking began in 2008.

That might have been but a precursor to the next pitching revolution we’re about to witness. This winter, people throughout the sport posited that 2024 could be the Year of the Splitter, as a long-forbidden pitch threatens a return to the mainstream.

“I feel like it was taboo for the longest time, right?” Tigers pitcher Casey Mize said. “It’s just whispers and conversations. ‘Hey, I really want to throw this pitch. How do you do it?’”

In the late 1970s, a minor leaguer named Hal Baird learned the splitter in a hotel conversation with Fred Martin, the coach who had taught it to Bruce Sutter. Sutter’s splitter carried him from Cubs farmhand to Hall of Famer.

Baird went on to coach at Auburn and continue proselytizing about the splitter. Most of his pitchers picked one up. John Powell set an NCAA strikeout record. Tim Hudson became an MLB All-Star. At Auburn years later, Mize was working to develop a third pitch, and Baird pupil Scott Sullivan passed along photos of his grip. Mize would be the No. 1 pick in the 2018 draft.

“I never knew anybody who had a really good one that didn’t find a way to be successful,” Baird said.

Bruce Sutter demonstrates his splitter grip after winning the 1979 Cy Young Award. (Photo by Bruce Bennett Studios via Getty Images Studios / Getty Images)

One morning inside the Reds clubhouse this spring, Cruz held his right hand to his thigh, his index and middle fingers spread wide in a “V” shape. As he talked about his splitter, he mimicked an exercise he uses to perfect the way he grips his best pitch. He has practiced it so many times, so many ways, it’s now habitual. He holds his iPhone like he’s gripping a splitter.

“If you want to get to the big leagues,” Cruz said, “you need something special.”

Cruz’s splitter was responsible for 80 of his 98 strikeouts last season, even though he threw the pitch only 35.9 percent of the time. He recorded the fifth-best strikeout rate of any MLB pitcher.

But Cruz does so with eyes wide open, fully conscious of its reputation and why it vanished for so long from the pitching landscape.

“It’s a life-changing pitch, no doubt,” he said. “But it could be the end of anybody’s career.”

In some ways, the splitter is viewed as a pitch of last resort. Cruz said he’s seen pitchers who throw splitters for a few years until “their elbow is completely gone.” He understood the risk. But he needed a way back into baseball, and thanks to the splitter, he finally broke into the big leagues 15 years after the Royals drafted him and after stints in Mexico, Puerto Rico, the Dominican Republic and independent ball.

Others who had major league stuff without a splitter shied away from it so as not to endanger their career. 

“I remember in Minnesota, it was a no-no,” former Twins and Tigers pitching coach Rick Anderson once said. “We were using it down there when we thought a guy might be running out of chances.”

But is it really as damaging as its reputation suggests? Even in this age of excess information, no one has cracked the secret to arm health. Dr. Keith Meister, a leading orthopedic surgeon and the Texas Rangers’ team physician, recently cited sweepers and other power changeups as reasons for spikes in arm injuries. A study from the Orthopedic Journal of Sports Medicine found velocity to have greater correlation to UCL injuries than pitch type.

“For some reason, we think (the splitter) is the singular cause of Tommy John, but whatever,” Mize said.

Casey Mize pitching in 2021, before his elbow surgery. (Adam Glanzman / Getty Images)

Mize underwent a UCL reconstruction in 2022, though he attributes his elbow issues to a back problem — which later required surgery — that led to mechanical issues.

“I talk to teammates who have had TJ and don’t throw a splitter,” he said, then turned sarcastic. “So OK. It’s not the fact that we’re throwing 100 (mph) every day?”

Royals pitching coach Brian Sweeney said it’s non-negotiable that if a pitcher is going to implement a splitter, he does so in the offseason. It requires a particular training of the forearm muscles. Sweeney said the Royals had a pitcher messing with a splitter earlier in camp, but they shut down the experiment out of fear of injury.

Baird taught his pitchers to spread their fingers only to a point of comfort and made sure their hands stayed behind the baseball as if throwing a normal fastball.

That variation is common to the modern-day splitter; pitchers no longer uniformly split their fingers wide to the degree Sutter did. Many pitchers employ alterations that make the pitch closer to a change-up than a true splitter. Former reliever Blake Parker threw several variations of a splitter for more than a decade, and said he occasionally experienced forearm soreness and stiffness between his index and middle fingers, but nothing debilitating.

Parker helped Stephan throw his splitter when they pitched together in Cleveland in 2021. Stephan spent that season as a Rule 5 draft pick buried in the bullpen, sometimes going a week or two without getting into a game. During Stephan’s downtime, Shaw taught him the splitter grip he learned from Putz. Parker, who’d learned his grip from former reliever Tyler Clippard, advised Stephan on the pitch’s mechanics and usage.

A year later, Stephan emerged as the Guardians’ setup man, and his splitter carried a whiff rate of 53.6 percent and an expected slugging percentage of .186. Hitters rarely touched the pitch, and when they did, they did nothing with it. That performance landed Stephan a four-year, eight-figure contract, two years after he was stuck in neutral in Double A.

“You see it work a few times,” Stephan said, “and then it’s your favorite pitch.”

Soon, though, Stephan will undergo elbow reconstruction surgery, wiping out his 2024 season. Was it the splitter that did it? Or everything else?

“I think there was a lot of anecdotal (evidence),” said Rays pitching coach Kyle Snyder, “people saying, ‘It’s bad for the elbow. It’s bad for the arm.’ Well, pitching is bad for the arm.”

When Roger Craig, another forerunner of the splitter, became Tigers pitching coach in 1980, he asked each pitcher to at least try the pitch. Four-fifths of the Tigers’ 1984 World Series-winning rotation used the splitter to varying degrees. Jack Morris used it to launch a Hall of Fame career.

Forty years after the Tigers’ last title, their pitching staff is again populated by splitter guys, with starter Kenta Maeda and reliever Shelby Miller signing this offseason and joining Mize. Miller learned the splitter last season after signing a minor-league deal with the Dodgers. Coaches told him the pitch would pair well with his penchant for elevated fastballs. Once approaching an early ending to a promising career, Miller posted a 1.71 ERA in relief for the Dodgers last year.

The reason for the splitter’s resurgence is not rooted in any reassessment of its health risks. It’s simpler than that:

“The numbers against it,” Miller said. “They’re great.”

Splitters leaguewide generated a 32.3 percent strikeout rate last season, higher than even the en vogue sweeper. MLB batters hit only .199 and generated a minus-74.3 run value against splitters, a pitch considered effective against both right-handed and left-handed batters. In a game where virtually everybody now throws high-90s fastballs, pitchers need to find another way to gain an edge.

“It’s crazy, this game,” Sweeney said. “Everything comes back around.”

Two trends might be fueling the revival at this particular time: the riding fastball and the launch angle revolution. With hitters reshaping their swings to connect with high heat, the splitter can sneak past them.

“A fastball delivery, a fastball arm speed,” said Cleveland pitching coach Carl Willis, “you see fastball out of the hand.”

“So now you throw the split,” added Cleveland manager Stephen Vogt, “and it’s gone.”

“It’s just there,” said Rockies catcher Jacob Stallings, “and then it’s not.”

There’s also the overseas influence. Shohei Ohtani uses his split as a putaway weapon. Kodai Senga’s “Ghost Fork” has devastating movement. High-profile international signings Yamamoto and Shota Imanaga are bringing splitters to MLB this season. Imanaga signed with the Cubs in an offseason several of their pitchers were trying splitters. Padres pitchers Yu Darvish and Yuki Matsui whirled splitters in the league’s opening game Wednesday, ahead of Yamamoto showcasing his own splitter in his Dodgers debut Thursday.

Goodness that Yamamoto Splitter is nasty pic.twitter.com/02wWgofamx

— 野球しようぜ (@7hodvj9oCM78910) March 1, 2024

But in today’s game, the pitch is not just an import.

“I think definitely more guys are throwing splitters here in the U.S., and I’m one of those guys,” Maeda said through an interpreter. “I never threw a splitter in Japan. That’s something I picked up here.”

There’s no universal splitter. Some resemble a sinking fastball, while others mirror a fading changeup, whichever variation best fits a pitcher’s arsenal and saddles hitters with another out pitch to dread.

Tyler Beede decided he needed to learn a split before he spent last year with the Yomiuri Giants in Japan, since the pitch is so prominent there. Now he’s back on U.S. soil in contention for a Guardians roster spot and considers his split, a harder version of his changeup, his top pitch.

“It acts as if it’s a left-handed slider,” he said. “It has that dive.”

And nowadays, the splitter isn’t just for those searching for a breakthrough.

Wheeler, Philadelphia’s ace, wanted another option to combat left-handed hitters, who logged a .722 OPS against him in 2023. Wheeler settled on the splitter after he and pitching coach Caleb Cotham decided his arm action wasn’t conducive to a typical changeup.

“I think this could put me over the top and hopefully get a Cy Young,” Wheeler told reporters in Clearwater, Fla.

Zack Wheeler, Disgusting 86mph Splitter. 🤮 pic.twitter.com/qQapwxFXyO

— Rob Friedman (@PitchingNinja) March 11, 2024

Even as the splitter spreads like it’s the ’80s all over again, it is not a pitch for everyone. Plenty of big-league pitchers have attempted to learn the pitch only to abandon it. Tigers ace Tarik Skubal had a failed flirtation with the pitch three springs ago. Padres starter Dylan Cease tried to learn Toronto ace Kevin Gausman’s splitter this offseason but couldn’t tame it. Sweeney spent three seasons testing it in Japan, but never mastered it.

“I never knew someone pick it up really, really well who didn’t pick it up quickly,” Baird said.

But for those who do master the splitter, it can become an asset unlike any other.

In 2021, 64 pitchers used the splitter in a major league game, according to Statcast. In 2022, 73 pitchers threw the split. Last season, the total increased to 84.

“Like I said, it was taboo, and there wasn’t a ton of volume,” Mize said, “so you had to find guys who threw them, and that’s where the conversations were had. Now we’ve got three, four guys in the clubhouse now, and that was not the case even a few years ago.”

— The Athletic‘s C. Trent Rosecrans and Chad Jennings contributed to this report.

(Top photo of Yamamoto’s splitter: Masterpress / Getty Images)